Question

Calculate the mass percent of different elements in sodium sulphate (Na₂SO₄).

Answer 1

Molar mass of sodium sulphate (Na₂SO₄)

= 2 x 23 + 32 + 4 x 16

= 46 + 32 + 64 = 142 u

Mass percent of sodium = 46 g/142 g x 100 = 32.39%

Mass percent of sulphur = 32 g/142 g x 100 = 22.53%

Mass percent of oxygen = 64 g/142 g x 100 = 45.07%